Can someone please explain to me what these markings mean and where this is from?

[Luke1777]

 

[FROGSMILE]

Shell case for an 18 Pounder Field Gun manufactured in 1917.  The 18 pounds refers to the weight of the projectile, which was army practice back then whereas we now follow the old naval practice of referring to the dimensions of the gun’s bore from which the shell is fired, e.g. 105mm.

Forum members @14276265 and @Peter Zieminski are subject matter experts who will be able to give you far greater detail. 

 

Edited 27 July , 2023 by FROGSMILE

[PhilB]

Was there much variation in the weights of projectiles that would normally be fired from a particular calibre of gun?

[FROGSMILE]

10 minutes ago, PhilB said:

Was there much variation in the weights of projectiles that would normally be fired from a particular calibre of gun?

As far as I know the projectile itself was the same weight within fine margins of manufacture.  The difference was in what the projectile did when it arrived at the target end, penetrative solid shot, high explosive fragmentation, or bursting shrapnel balls.  They had to be the same in order to have consistent ballistic properties and thus fired with the same charge and on the same line and trajectory.  That enabled mixed munitions to be fired at the same target for maximum effect.

Edited 27 July , 2023 by FROGSMILE

[PhilB]

Thanks, Frog. I had assumed that, on a particular gun, the gunners would have a range of ballistics and trajectory figures for various weights of charge.

[FROGSMILE]

39 minutes ago, PhilB said:

Thanks, Frog. I had assumed that, on a particular gun, the gunners would have a range of ballistics and trajectory figures for various weights of charge.

Yes the charge when combined with the angle of elevation was aligned with range tables, that’s correct, but the projectiles themselves were the same weight and you either added, or reduced charges, to increase, or reduce range.

Edited 27 July , 2023 by FROGSMILE

[peregrinvs]

Possibly a Canadian manufactured case if that’s a broadarrow in a C marking at 10 o’clock. 

[14276265]

On 27/07/2023 at 18:29, PhilB said:

Was there much variation in the weights of projectiles that would normally be fired from a particular calibre of gun?

There was variation in weights of filled shell (both fixed and separate loading ammunition) which was compensated for in the gun and howitzer range tables.

For example, 18pr shrapnel used various marks of shell and various marks of No.80 fuze (and also single mark of No.85 for a while), all with different weights; a No.80 fuze made of brass and steel was far heavier than one made mostly of aluminium. Light shell were generally married with heavy fuzes and vice versa to create a "Normal" weight range of 18lb 3oz to 18lb 10oz. Heavy shell were also married with heavy fuzes to make a "Heavy" weight range of mean 19lb 4oz. Packaging and fuze covers were marked with identifying colours.

For the larger natures of 60pr and above, weight bands were defined and stencilled on the shell: for example +1, 0, -1 for 60pr; 0, -1, -2 for 9.2-inch. Again the range tables referred.

Edit to add: range table for 18pr weights attached

 

265

 

Edited 28 July , 2023 by 14276265
Range table added

[FROGSMILE]

This description perfectly epitomises what I meant:

“Light shell were generally married with heavy fuzes and vice versa to create a"Normal" weight range [for the projectile] of 18lb 3oz to 18lb 10oz.” The relatively minor differential is thus manageable within ballistic properties.

Edited 28 July , 2023 by FROGSMILE